Hi Amy. I am so glad you are alert to changes in your bird's appearance and that you have come to ask about it. Unfortunately yes, this could be a very serious symptom. To my knowledge, this is a relatively new finding in Budgie studies but, apparently, an adult male budgie whose cere turns from blue to brown could have testicular cancer.
This makes sense, because the testes produce testosterone, and without testosterone, feminization can occur, in humans, anyway. As I'm sure you know, the female cere color is in the "brown family", pale tan, cream color, brown, etc. I read somewhere else that tumours do not usually appear in budgies under three yers of age. I am not sure what the age statistics are for testicular cancer. In any case, I think a discussion with your avian vet is in order, asap. It also makes sense because Budgies, especially those on all seed diets, (a huge no-no) are very susceptible to tumors and liver disease. If you bird happens to be on an all seed diet, he is particularly at risk. I think it would be reasonable to assume that the more prone a bird is to tumors of any kind, then it would follow the more possibly prone they are to cancers. I hope this is not the case with your guy but I would get him in for a check up right away, just to be on the safe side. I hope this is helpful information but if you have any further questions, don't hesitate to ask. Patricia
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